Recreating a specific JSON structure

Question

I am attempting to recreate the below JSON in JAVA.

[{                  
"Operation": {
    Product: "MyProduct",
    Noun: "MyNoun",
    Verb: "MyVerb"
},
"Authentication": {
    UserID: "UserName",
    Password: "Password"
}}]

I feel like the Maps are the way to go. But I am having trouble forming the proper structure.

Map<String,String> opsDictionary =  new HashMap<String,String>();
    opsDictionary.put("Product","MyProduct");
    opsDictionary.put("Noun","MyNoun");
    opsDictionary.put("Verb", "MyVerb");

Map<String,String> authDictionary =  new HashMap<String,String>();
    authDictionary.put("UserID","UserName");
    authDictionary.put("Password", "Password");


JSONObject postdata = new JSONObject();
postdata.put("Operation", opsDictionary);
postdata.put("Authentication", authDictionary);

Which spits out this INCORRECT version:

{
    "Authentication": "{UserID=CADEMO, Password=TESTPASSORD}",
    "Operation": "{Noun=User, Product=TOPSInventory, Verb=Authenticate}"
}

I toyed with the idea of packaging up the Maps in a bundle

Bundle dataBundle = new Bundle();
dataBundle.putStringArray("Operation", opsDictionary);
dataBundle.putStringArray("Authentication", authDictionary);

What am I doing wrong?

I was able to replicate this format in my iOS version using Dictionaries.

 NSMutableDictionary * dicOperation = [[NSMutableDictionary alloc]init];
    [dicOperation setValue:product forKey:@"Product"];
    [dicOperation setValue:noun    forKey:@"Noun"];
    [dicOperation setValue:verb    forKey:@"Verb"];

    NSMutableDictionary * dicAuthentication = [[NSMutableDictionary alloc] init];
    [dicAuthentication setValue:username   forKey:@"UserID"];
    [dicAuthentication setValue:password forKey:@"Password"];


    NSData* jsonData = [NSJSONSerialization dataWithJSONObject:dictPackage options:NSJSONWritingPrettyPrinted error:&error];

I was hoping there was a similar solution for Android.

Answer 1

You do not need to use Hashmap. That is probably what is causing the string concatenated results.

It should read this

JSONObject opsDictionary = new JSONObject();
    opsDictionary.put("Product","MyProduct");
    opsDictionary.put("Noun","MyNoun");
    opsDictionary.put("Verb", "MyVerb");


JSONObject authDictionary = new JSONObject(); 
    authDictionary.put("UserID","UserName");
    authDictionary.put("Password", "Password");


JSONObject postdata = new JSONObject();
postdata.put("Operation", opsDictionary);
postdata.put("Authentication", authDictionary);

And if you are intending to create an array, finally attach to an array (in a loop or as required):

JSONArray ja = new JSONArray();
ja.put(postdata );

Code usage from How to create correct JsonArray in Java using JSONObject

Answer 2

I'm not sure for my answer. Since i use jsonobject, jsonarray and Gson library, I worked only with simple object (string, boolean, number etc...), custom objects defined by "{}" and array of custom object.

Inside an array all element (custom or not) have got the same structure. So che fields of the first element are the same of second one. In your case I see only an associative array, not a real array. I'm not sure Gson or json provide, or are useful for your data. Maybe you have to use a custom object calles X wheere inside there are 2 custom object called Y and Z, because Y and Z have got different structure.

But I repeat...maybe my idea is wrong.

Answer 3

you can do that by creating the proper structure of the json using classes the serialize , deserialize as you need.

first class MyOperation

public class MyOperation{
    private String Product = "";
    private String Noun = "";
    private String Verb = "";

    //setters and getters
}

second class MyAuthentication

public class MyAuthentication{
    private String UserID = "";
    private String Password = "";

    //setters and getters
}

and the -holder- class MyContent

public class MyContent{
    private MyOperation Operation = new MyOperation();
    private MyAuthentication Authentication = new MyAuthentication();

    //setters and getters
}

your JSON is an array of type MyContent you can serialize, deserialize using Gson:

//serialize example
MyContent myContent[] = new MyContent[1];
myContent[0] = new MyContent();
myContent[0].setMyOperation(....);
myContent[0].setMyAuthentication(....);

Gson gson = new Gson();
String jsonString = gson.toJson(myContent, MyContent[].class);

Answer 4

The JSON you report is not valid. It doesn't matter what you have, if you want to work with JSON you have to follow JSON rules. If you have doubt about the format, you can check it here

Some working format could be something like this

{
     "Operation": [
    {
      "Product": "MyProduct",
      "Noun": "MyNoun",
      "Verb": "MyVerb"
    }
  ],
       "Authentication": [
      {
      "UserID": "UserName",
      "Password": "Password"
    }
  ]
}

In general, JSON can be thought as a Tree. Every node of the tree can be:

• an item

  {
  "item1Name": "item1Value",
  "item2Name": "item2Value",
  ...
  }
  

• an array

  [
  "val1",
  "val2",
  ...
  ]
  

• a subnode

  {
  "array": ["arrayitem1", ...],
  "itemX": "itemXValue",
  ...
  }
  

proper values can be numbers or strings, proper "keys" can be just strings.

In Java, you can easily map the items as Map<String, String> and arrays as List<Map<String,String>>

EDIT: once you get the right classes in the structure, you have to use the proper serializer. Otherwise toString() will be called and the wrong result (as you showed) will come out